Personally I like to have two dogs. From my experience of having just 1 and comparing it to the times when I have 2 I have noticed that the dogs certainly get something 'extra' out of life shared with another dog that we just can't give them. I certianly applaud your idea to rescue a dog and I wouldn't be put off having 2 dogs to share your home with.

A dog walker is an option. What is the best way of finding one in my area :  I did look in the local paper and didn't see any.

Apart from Kongs and food cubes, are there any other good ways of keeping a dog amused/busy whilst he is on his own :  He has a ball and squeeky but will only play with them when I am there.

I've got two dogs and I also think they get something extra out of life by having one of their own kind to play with and be with.

BUT, as dogmad says, you could end up with two bored dogs instead of one, barking (and potentially destroying the house) if they're left alone for 9 hours a day.  9 hours is an awfully long time to be left alone during the day, from the perspective of not going to the toilet for that length of time if nothing else.  I don't think I could not go to the toilet for 9 hours during the day!!

You could try your vets notice board to find a dog walker?  Or if you search the net, there are a lot of professional pet sitting franchises about, but I've not used one so don't know how good they would be.

Good luck though with whatever you decide to do and do let us know how you get on  

Sorry to nip in on this one with no real advice (you have great advice already!), I just wondered - does your collie stay outside while you're not there?

It might be worthwhile keeping them indoors while no-one's about - as dog thieves are very common nowadays, especially for working dogs or pedigrees  

Best of luck